Question

Give an example of an ecosystem where the pyramid of biomass is inverted.

Hint:

Think about producers that are tiny and short-lived but still support a heavier population of consumers.

Answer 1

Step 1: Recall what an inverted pyramid of biomass means.
A pyramid of biomass normally narrows as it goes up, since producers usually outweigh the consumers that eat them. An inverted pyramid happens when the producer level has a smaller total mass than the consumers feeding on it, at the moment it is measured.

Step 2: Apply this to a pond ecosystem.
In a pond, the producers are tiny, fast reproducing phytoplankton, so their standing crop (mass present at one time) is small, even though they are eaten and replaced very quickly. The zooplankton and fish feeding on them build up a larger standing biomass than the phytoplankton they depend on.

Step 3: State the result.
So if you weigh all the organisms at each level at a single moment, the pond's producer level looks lighter than the consumer levels above it, giving an inverted, top heavy pyramid shape.

Final Answer:
A pond (or a marine) ecosystem is a standard example of an inverted pyramid of biomass.